vchkpw eats 99% of cpu time

[Cajus Pollmeier]

Hi all!

I've got a little [well it grows ;-)] problem with vchkpw. Thats my setup:

qmail 1.03 + qmailqueue-patch
scan4virus 0.94
vpopmail 4.9.8
ucspi-tcp 0.88
daemontools 0.70

Starting with svscan with something like this in 
/var/qmail/supervise/qmail-pop3/run:

#!/bin/sh
HOSTNAME=`hostname -f`
exec /usr/local/bin/softlimit -m 20000000 \
        /usr/local/bin/tcpserver -v -p -x /etc/tcp.smtp.cdb \
        0 pop-3 /var/qmail/bin/qmail-popup $HOSTNAME \
        /home/vpopmail/bin/vchkpw /var/qmail/bin/qmail-pop3d ./Maildir/ 2>&1

In 90% of all cases popping the mails works fine. The other 10% create a 
vchkpw process consuming 99% cpu time, staying there till I send a SIGKILL.

Any solutions for this scenario?

Thanks in advance,
-Cajus